The long-term aim of this research is to increase the appropriate use of alcohol screening and brief intervention (Bl) in primary care settings. In order to make screening and Bl practical, clinicians need brief and efficient ways to identify primary care patients with hazardous and problem drinking, and distinguish patients appropriate for Bl from those with alcohol dependence for whom referral may be indicated. We previously described and validated a brief, 3-item alcohol-screening questionnaire (the AUDIT-C) in female and male VA outpatients, and showed that it could help identify patients with hazardous drinking as well as those with severe problem drinking. The proposed study will evaluate the AUDIT-C in a non-VA population, using secondary data from a large NIAAA-funded study by Volk and colleagues. 1-5 The Specific Aims of the proposed project are: 1) To evaluate the AUDlT-C as a screening test for hazardous drinking and/or active alcohol abuse or dependence based on interviews, and compare its performance with those of 3 existing screening tests, 2) To identify optimal screening thresholds (cut-points) for the AUDIT-C to detect hazardous drinking and/or active alcohol abuse or dependence, and 3) To evaluate two previously proposed strategies that use the AUDIT-C or the full, 10-item AUDIT to identify the subset of screen-positive patients who have past-year alcohol dependence. To achieve these aims, the proposed study will compare screening questionnaires, and strategies to identify alcohol dependent patients, to "gold" standards based on the Alcohol Use Disorders and Associated Disabilities Interview Schedule (AUDADIS). Sensitivity, specificity, likelihood ratios, and areas under Receiver Operating Characteristic (ROC) curves, will be used to evaluate each screening test. Optimal screening thresholds will be identified for a range of assumptions about prevalence rates and cost-benefit ratios for alcohol screening. Efficient methods for 1) alcohol screening and 2) identifying the subgroup of screen-positive patients, who are known to benefit from Bl, will contribute to the clinical implementation of screening and Bl, and facilitate future research on strategies to promote these evidence-based practices.